Slag cement and method of making the same.



r'rnNr eerie.

. SHINN, or rrr'rseune, PENNSYLVANIA:

SH -G CEMENT AND METHOD OF MAKING THE SAME.

To aZZ whom; it may concern.-

Be it known that i, Josnrn A. SHINN, of Pittsburg, in the county of Allegheny and State of Pennsylvania, have invented a new and useful Slag Cement and Method of Making the Same, of which the following is a full, clear, and exact description.

My invention relates to that class of cements wherein ground slag is intimately mixed with lime; and its object is to provide a dry cement composition which may be shipped in bulk to the point of use and there mixed with sand and Water to give a mortar and to improve the appearance, strength, and specific gravity of previous compositions of this general character.

In carrying out my invention I use as a base a strongly-basic slagthat is, one having a preponderance of alumina or lime, or both. I granulate this slag in the Welllmown manner by means of a stream of water, and I then add to this granular basic slag lime in the form of calcium hydrate and also dehydrated oXid of iron. The oxid 'of iron may be in the form of flue-dust, which is composed of finely-divided iron ore, or in the form of mill-scale or roasted iron ore.- The proportionswhich I prefer to employ are seventy-dive to ninety parts of" the granulated slag, ten to twenty parts of lime, and three to fifteen parts of iron oxid, these parts being by weight. These proportions may of course be varied, according to the character of the slag and the results desired. This composition having been made up is ground in a tube-mill or similar apparatus to such a finely-pulverized condition that over ninety percent. of it will pass through a two-hundred-mesh screen. This product is then made 11 in packages of the esiredjsize and'forms t e-cement base which is shipped to the users.

In usin this cement composition it is mired with frorn two to six parts of sand with water, this gvet mortar then being used in the usual way. J

I prefer to use iron oXid in the form'of millscale because of the improved color which is imparted to the cement and mortar, it'being Specification of Letters Patent.

Application filed July 8, 1901- Sarial No. 67.544.

sic slag, ten to twenty parts of hy Patented March 27, 1906.

of'a grayish color, closely a proximating the colorof Portland cement'an graystone. The flue-dust or iron ore gives a reddish color, which is not. considered as desirable in cements as the grayish-color for some classes or work.

The advantages of my invention result from the use of the iron oxid in the finelypulverized dry mixture, since this greatly improves the. strength, specific gravity and hardnessof the mortar made up from t e c'e ment. Actual tests of this material have proved its superiority over the usual forms of sla cements containing only pulverized slag nd lime as the cementitious base.

Variations may be made in the proportions above named and in the particular slag and form of iron oxid used Without departing from my invention.

1. The method of making slag-cement consisting in granulating basic slag, mixing this Igranulated slag with hydrated lime and deydrated iron oXid and drygrinding the mixture sufficiently fine that at least ninet per cent. will pass through a two-hundre mesh screen; substantially as described.

2. The method of making slag-cement, consisting in mixing granulated basic slag, drated lime, and dehydrated iron oxid 1n tile following proportions: seventy-five to ninety parts of slag, ten to twenty'parts of lime, and three to fifteen parts of iron oxid, and then dry-grinding themixture; substantially as described.

3. As a new composition of matter, a slagcement consisting of a finely-ground mixture containing seventy-five to ninety arts of barated lime, and three to fifteen parts of iron oxid; substantially as described.

In testimony whereof I have hereunto set 0 my hand. I

v JOSEPH A. SHINN. .Witnes ses:

GEO. B. BLEMING,

O. P. BYRNESr 

